PAPIMonitor (Python API Monitor for Android apps) is a python tool based on Frida for monitoring user-select APIs during the app execution. The app should be installed within an emulator already connected through ADB to the pc host. The user can choose to monitor a predefined list of APIs divided into several categories (e.g., Device Data, Device Info, SMS) or a custom list of APIs passed through the command line to the script. The tool stores the invoked API, the parameters, the return value, and the line and file from where it was called.

Below is an example of output:

{   
    "category": "Custom", 
    "class": "com.dave.popupre.MainActivity", 
    "method": "getText", 
    "args": [], 
    "calledFrom": "com.dave.popupre.MainActivity$1.onClick(MainActivity.java:26)", 
    "returnValue": "Hello Toast!", 
    "time": "03/09/2021, 14:43:06"
}

⚠️ Warning with Google Emulator

⚠️ Frida seems broken on Android 11-12 (x86_64) (Google Emulatore).

• issue-1917
• issue-1977
• issue-1982

General requirements:

sudo apt-get install libjpeg-dev zlib1g-dev

• Install pyenv and pyenv-virtualenv

pyenv install 3.8.0
pyenv virtualenv 3.8.0 papi-monitor
pyenv activate 3.8.0/envs/papi-monitor
pip3 install -r requirements

• install virtualenv

sudo apt-get install python3-virtualenv

• activate virtualenv

virtualenv env
source env/bin/activate

• install requirements

pip install -r requirements

• Download frida-server in resources/frida-server/

• adb in path file
• emulator/device already running and connect

python papi_monitor.py --package-name com.package.name --filter "Crypto"
python papi_monitor.py --file-apk app.apk --api-monitor api_personalized.json
python papi_monitor.py --package-name com.package.name --api-monitor api_personalized.json
python papi_monitor.py --package-name com.package.name --filter "ALL"
python papi_monitor.py --package-name com.package.name --api-monitor api_personalized.json --store-script True --filter "Crypto" "Crypto - Hash"
python papi_monitor.py --package-name com.package.name --api-monitor api_personalized.json --pinning-bypass --antiroot-bypass     

• Device Data
• Device Info
• SMS
• System Manager
• Base64 encode/decode
• Dex Class Loader
• Network
• Crypto
• Crypto - Hash
• Binder
• IPC
• Database
• SharedPreferences
• WebView
• Java Native Interface
• Command
• Process
• FileSytem - Java

A lot of Frida Script for Android can be found here.